Washers 10/20/50/100PCS Bonded Stainless Steel Roofing Washers Composite Waterproof and Non-Slip Gasket : Amazon.ca: Tools & Home Improvement
Source zinc Roofing screws with EPDM washer or common washer on m.alibaba.com
High performance metal roof washer suits fastener gauge #14 - Black O.D 19mm | Manufacturer of roof flashings, plumbing and civil water infrastructure products and rubber washers - DEKS Industries
High performance metal roof washer suits fastener gauge #14 - Black O.D 32mm | Manufacturer of roof flashings, plumbing and civil water infrastructure products and rubber washers - DEKS Industries
Roofing Sheet Fitting Bitumen Washer, Round
Otter Dome Washer - Screws | Mitre 10™
Teks #9 x 1-1/2 in. External Hex Zinc Plated Steel Hex Washer Head Roofing Screws (100-Pack) 21404 - The Home Depot